intermittent fasting

What is Intermittent Fasting?

Buckle up, people because this is one helluva post. Intermittent fasting is not a new concept but has been a topic of more and more conversations in and out of the fitness space. I did a quick 101 on intermittent fasting a while back if you haven’t already done so take a quick read here before you go any further.

I SWEAR by intermittent fasting (IF) and attribute it to a great deal of my success in changing my body, simplifying (!!!) my lifestyle, and improving my metabolism.

Okay, okay. Let’s get into this.

WHAT is Intermittent Fasting?

Intermittent fasting is a lifestyle that cycles between periods of eating (or feeding) and fasting. The focus of IF isn’t what you consume but when you eat. It’s NOT a diet, there are no restricted foods, and it’s certainly NOT caloric deprivation (calculate your daily caloric needs here). Intermittent fasting cycles include 10, 12, or 16-hour fasts but can vary for your individual needs and goals. I’ll caveat that some people who practice IF will incorporate a 24-hour fast, which I DO NOT do. HELL. NO. The following speaks of a 24-hour period that includes both a fast and feed.

To be clear, when you fast you are NOT consuming calories. None. Nada. Zilch. You’re drinking water to stay hydrated, it’s crucial to stay hydrated in general but especially when practicing IF. Herbal tea or black coffee* is also acceptable. When you feed, you ARE consuming all of your calories for the day in your desired feeding window.

*It can be argued that consuming bulletproof coffee (or any variation of a full-fat source) will not break your fast as fat does not stimulate insulin production.

HOW do you Implement an Intermittent Fasting program?

IF seems like this complicated method but it’s not, hence the ability to simplify your lifestyle. There’s a window of time where you eat and then anything outside of that you’re not eating. It’s black and white. Either you’re eating, or you’re not.

Before you do anything, you have to establish your feeding window. To do this, carefully consider your lifestyle. For me, I workout and train my clients in the morning. To do that I need to have any empty stomach – that’s what works for me. I also train clients in the evening and therefore eat after 7 PM at the earliest. Again that’s what works for me. My feeding window is from 12PM-8PM to accommodate my schedule.

If you’ve never fasted before, I do not recommend an 8-hour feeding window. It’s too aggressive. Instead, start with a 12-hour window for a week, progress to a 10-hour window for a week and work your way down to an 8-hour feeding window. IF is flexible in the sense that you can choose your feeding window, but to be successful you need at least 12 hours between your last meal of the day and your first meal of the following day. I’ve been fasting for over two years and have found that a feed window for 8-hours followed by a 16-hour fast window is my sweet spot.

When you’re establishing your feed window here are a few things to consider:

  • When you workout, especially if you’re the type of person that needs to eat directly before or after. Your pre and post-workout meals COUNT and will break your fast.
  • Your work schedule, when you’ll be available to eat? Can you eat whenever you want? Or do you have to plan your meals around a break schedule?
  • Needs of friends or family. If eating a meal with your family is important to you, make sure to build it into your feed cycle.
  • Sleep! IMO the best way to fast is to do it while you sleep. WINK. 

WHY Should you Intermittent Fast?

It takes roughly eight hours to metabolize your glycogen stores (carbohydrates), and after that, your body will need to burn another source for fuel. If you are not replacing those glycogen stores (eating more carbs), your body will start to burn its fat stores. YES!

Your body’s journey with IF looks like this. Your body can use energy from its last meal of the day for about 6 hours, maybe eight depending on what you’ve consumed. For the next six or seven hours, your body will use its blood sugar for fuel and two-ish hours after that will start to burn fat until you refeed. Your body will fully deplete its glycogen and blood sugar stores and turn to burn fat for fuel. That’s why I recommend clients experiment with a high-fat diet. If you’re feeding your body fat, as opposed to carbs to break your fast especially, your body will continue to burn fat for fuel.

That’s also why I recommend clients experiment with a high-fat diet. If you’re feeding your body fat, as opposed to carbs to break your fast especially, your body will continue to burn fat for fuel.

It’s important to note that IF is not a magic solution for weight or fat loss. IF is a way to manage your intake, and consolidates consumption. In fact, in multiple studies conducted earlier this year in subjects whose goal was weight loss revealed no significant advantage between those who practiced IF and those who didn’t.

WHEN do you Fast or Feed?

Consistency is key. The more you do, the quicker your metabolism will be. And, like any lifestyle adjustment, it takes a second to adapt. You’re not going to wake up and be like “OMFG I FEEL AMAZING.” You’ll most likely wake up and be like “OMFG I’M STARVING HOW AM I GOING TO HOLD OUT UNTIL 1 PM TO EAT?!” That’s to be expected, which is why it helps to ease into your fast cycles starting at 12, working to 10-hours, then 8-hours at a time. You have to decide your cycle. What works for me may not work for you, and what works for you may not work for me. AND THAT’S OKAY.

WHO Should Consider Intermittent Fasting?

Literally – anyone! I found it helpful when I worked in advertising full time. If you’re traveling around the clock, entertaining clients, chained to a craft service table, and have very little time to exercise IF can save you.

Our society revolves around meals and eating. Society dictates our eating schedule, and honestly, the hardest part about starting an IF lifestyle is breaking through those societal norms. Don’t feel pressured to eat. IF is a lifestyle change that will take some time for acclimation, mentally, physically and emotionally. But I would be shocked if you didn’t feel better every day. Give it a try, and let me know how you do.


Image via Fitted Magazine


  1. Hi Kate! Thanks for the great article. I’ve been macro counting for (about) 6 weeks (not totally strict the last couple weeks). Do you believe IF is more effective than macro counting, or should we be doing both together?

  2. Do you incorporate tracking your macronutrients in addition to your intermittent fasting daily?

  3. Hi! Do you drink your fatty coffee in the morning with IF? Does that count towards your “feeding” time?

    • I do drink it in the morning while fasting. Because it is a full-fat source and my diet is typically high in fat I do NOT count this towards my feed window. If your macros are evenly split or you’re not tracking marcos I would count this towards your feed time and this would break your fast.

  4. Hi Kate,

    Do you just do 2 meals with IF or do you eat snacks too? I’m going to start doing IF and need all the help I can get 🙂

Leave a Comment

Your email address will not be published. Required fields are marked *